Data encryption parameter dispersal

ABSTRACT

A method for securely distributing a profile within a dispersed storage network (DSN) that begins by encrypting a profile using a key. The method continues by encoding the encrypted profile in accordance with a dispersed storage error encoding function. The method continues by outputting the set of encoded profile slices to the DSN for storage therein. The method continues by encoding the key in accordance with an error encoding function and outputting the set of secure key portions to a set of devices of the DSN for storage therein. A device obtains the profile by retrieving secure key portions from the set of devices and recovering the key therefrom. The device then retrieves encoded profile slices from the DSN and decodes them to recover the encrypted profile. The device then decrypts the encrypted profile using the key to recover the profile.

CROSS REFERENCE TO RELATED PATENTS

The present U.S. Utility Patent Application claims priority pursuant to35 U.S.C. § 120, as a continuation, to the following U.S. Utility PatentApplication which is hereby incorporated herein by reference in itsentirety and made part of the present U.S. Utility Patent Applicationfor all purposes:

-   -   1. U.S. Utility application Ser. No. 12/885,160, entitled “DATA        ENCRYPTION PARAMETER DISPERSAL,” filed Sep. 17, 2010, now U.S.        Pat. No. 8,468,368, which claims priority pursuant to 35 U.S.C.        § 119(e) to the following U.S. Provisional Patent Application        which is hereby incorporated herein by reference in its entirety        and made part of the present U.S. Utility Patent Application for        all purposes:        -   a. U.S. Provisional Application Ser. No. 61/290,689,            entitled “DISTRIBUTED STORAGE WITH DATA SECURITY,” filed            Dec. 29, 2009.

STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT

Not Applicable

INCORPORATION-BY-REFERENCE OF MATERIAL SUBMITTED ON A COMPACT DISC

Not Applicable

BACKGROUND OF THE INVENTION Technical Field of the Invention

This invention relates generally to computing systems and moreparticularly to data storage solutions within such computing systems.

Description of Related Art

Computers are known to communicate, process, and store data. Suchcomputers range from wireless smart phones to data centers that supportmillions of web searches, stock trades, or on-line purchases every day.In general, a computing system generates data and/or manipulates datafrom one form into another. For instance, an image sensor of thecomputing system generates raw picture data and, using an imagecompression program (e.g., JPEG, MPEG, etc.), the computing systemmanipulates the raw picture data into a standardized compressed image.

With continued advances in processing speed and communication speed,computers are capable of processing real time multimedia data forapplications ranging from simple voice communications to streaming highdefinition video. As such, general-purpose information appliances arereplacing purpose-built communications devices (e.g., a telephone). Forexample, smart phones can support telephony communications but they arealso capable of text messaging and accessing the Internet to performfunctions including email, web browsing, remote applications access, andmedia communications (e.g., telephony voice, image transfer, musicfiles, video files, real time video streaming. etc.).

Each type of computer is constructed and operates in accordance with oneor more communication, processing, and storage standards. As a result ofstandardization and with advances in technology, more and moreinformation content is being converted into digital formats. Forexample, more digital cameras are now being sold than film cameras, thusproducing more digital pictures. As another example, web-basedprogramming is becoming an alternative to over the air televisionbroadcasts and/or cable broadcasts. As further examples, papers, books,video entertainment, home video, etc. are now being stored digitally,which increases the demand on the storage function of computers.

A typical computer storage system includes one or more memory devicesaligned with the needs of the various operational aspects of thecomputer's processing and communication functions. Generally, theimmediacy of access dictates what type of memory device is used. Forexample, random access memory (RAM) memory can be accessed in any randomorder with a constant response time, thus it is typically used for cachememory and main memory. By contrast, memory device technologies thatrequire physical movement such as magnetic disks, tapes, and opticaldiscs, have a variable response time as the physical movement can takelonger than the data transfer, thus they are typically used forsecondary memory (e.g., hard drive, backup memory, etc.).

A computer's storage system will be compliant with one or more computerstorage standards that include, but are not limited to, network filesystem (NFS), flash file system (FFS), disk file system (DFS), smallcomputer system interface (SCSI), internet small computer systeminterface (iSCSI), file transfer protocol (FTP), and web-baseddistributed authoring and versioning (WebDAV). These standards specifythe data storage format (e.g., files, data objects, data blocks,directories, etc.) and interfacing between the computer's processingfunction and its storage system, which is a primary function of thecomputer's memory controller.

Despite the standardization of the computer and its storage system,memory devices fail; especially commercial grade memory devices thatutilize technologies incorporating physical movement (e.g., a discdrive). For example, it is fairly common for a disc drive to routinelysuffer from bit level corruption and to completely fail after threeyears of use. One solution is to use a higher-grade disc drive, whichadds significant cost to a computer.

Another solution is to utilize multiple levels of redundant disc drivesto replicate the data into two or more copies. One such redundant driveapproach is called redundant array of independent discs (RAID). In aRAID device, a RAID controller adds parity data to the original databefore storing it across the array. The parity data is calculated fromthe original data such that the failure of a disc will not result in theloss of the original data. For example, RAID 5 uses three discs toprotect data from the failure of a single disc. The parity data, andassociated redundancy overhead data, reduces the storage capacity ofthree independent discs by one third (e.g., n−1=capacity). RAID 6 canrecover from a loss of two discs and requires a minimum of four discswith a storage capacity of n−2.

While RAID addresses the memory device failure issue, it is not withoutits own failure issues that affect its effectiveness, efficiency andsecurity. For instance, as more discs are added to the array, theprobability of a disc failure increases, which increases the demand formaintenance. For example, when a disc fails, it needs to be manuallyreplaced before another disc fails and the data stored in the RAIDdevice is lost. To reduce the risk of data loss, data on a RAID deviceis typically copied on to one or more other RAID devices. While thisaddresses the loss of data issue, it raises a security issue sincemultiple copies of data are available, which increases the chances ofunauthorized access. Further, as the amount of data being stored grows,the overhead of RAID devices becomes a non-trivial efficiency issue.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING(S)

FIG. 1 is a schematic block diagram of an embodiment of a computingsystem in accordance with the invention;

FIG. 2 is a schematic block diagram of an embodiment of a computing corein accordance with the invention;

FIG. 3 is a schematic block diagram of an embodiment of a distributedstorage processing unit in accordance with the invention;

FIG. 4 is a schematic block diagram of an embodiment of a grid module inaccordance with the invention;

FIG. 5 is a diagram of an example embodiment of error coded data slicecreation in accordance with the invention;

FIG. 6 is a schematic block diagram of an embodiment of a post-slicede-manipulator in accordance with the invention;

FIG. 7 is a flowchart illustrating an example of determining slices inaccordance with the invention;

FIG. 8 is a table illustrating an example of an access-ID-to-record-IDtable in accordance with the invention;

FIG. 9 is another schematic block diagram of another embodiment of acomputing system in accordance with the invention;

FIG. 10 is another schematic block diagram of another embodiment of acomputing system in accordance with the invention;

FIG. 11 is a flowchart illustrating an example of encrypting and storingof encoded data slices in accordance with the invention;

FIG. 12 is a flowchart illustrating an example of retrieving anddecrypting encoded data slices in accordance with the invention;

FIG. 13 is another flowchart illustrating another example of encryptingand storing of encoded data slices in accordance with the invention;

FIG. 14 is another flowchart illustrating another example of retrievingand decrypting encoded data slices in accordance with the invention;

FIG. 15 is another schematic block diagram of another embodiment of acomputing system in accordance with the invention;

FIG. 16 is a schematic block diagram of an embodiment of an encryptionkey storage and retrieval system in accordance with the invention;

FIG. 17 is a flowchart illustrating an example of storing an encryptionkey in accordance with the invention;

FIG. 18 is a flowchart illustrating an example of retrieving anencryption key in accordance with the invention; and

FIG. 19 is a flowchart illustrating an example of retrieving a secrettransformation in accordance with the invention.

DETAILED DESCRIPTION OF THE INVENTION

FIG. 1 is a schematic block diagram of a computing system 10 thatincludes one or more of a first type of user devices 12, one or more ofa second type of user devices 14, at least one distributed storage (DS)processing unit 16, at least one DS managing unit 18, at least onestorage integrity processing unit 20, and a distributed storage network(DSN) memory 22 coupled via a network 24. The network 24 may include oneor more wireless and/or wire lined communication systems; one or moreprivate intranet systems and/or public internet systems; and/or one ormore local area networks (LAN) and/or wide area networks (WAN).

The DSN memory 22 includes a plurality of distributed storage (DS) units36 for storing data of the system. Each of the DS units 36 includes aprocessing module and memory and may be located at a geographicallydifferent site than the other DS units (e.g., one in Chicago, one inMilwaukee, etc.). The processing module may be a single processingdevice or a plurality of processing devices. Such a processing devicemay be a microprocessor, micro-controller, digital signal processor,microcomputer, central processing unit, field programmable gate array,programmable logic device, state machine, logic circuitry, analogcircuitry, digital circuitry, and/or any device that manipulates signals(analog and/or digital) based on hard coding of the circuitry and/oroperational instructions. The processing module may have an associatedmemory and/or memory element, which may be a single memory device, aplurality of memory devices, and/or embedded circuitry of the processingmodule. Such a memory device may be a read-only memory, random accessmemory, volatile memory, non-volatile memory, static memory, dynamicmemory, flash memory, cache memory, and/or any device that storesdigital information. Note that if the processing module includes morethan one processing device, the processing devices may be centrallylocated (e.g., directly coupled together via a wired and/or wireless busstructure) or may be distributedly located (e.g., cloud computing viaindirect coupling via a local area network and/or a wide area network).Further note that when the processing module implements one or more ofits functions via a state machine, analog circuitry, digital circuitry,and/or logic circuitry, the memory and/or memory element storing thecorresponding operational instructions may be embedded within, orexternal to, the circuitry comprising the state machine, analogcircuitry, digital circuitry, and/or logic circuitry. Still further notethat, the memory element stores, and the processing module executes,hard coded and/or operational instructions corresponding to at leastsome of the steps and/or functions illustrated in FIGS. 1-19.

Each of the user devices 12-14, the DS processing unit 16, the DSmanaging unit 18, and the storage integrity processing unit 20 may be aportable computing device (e.g., a social networking device, a gamingdevice, a cell phone, a smart phone, a personal digital assistant, adigital music player, a digital video player, a laptop computer, ahandheld computer, a video game controller, and/or any other portabledevice that includes a computing core) and/or a fixed computing device(e.g., a personal computer, a computer server, a cable set-top box, asatellite receiver, a television set, a printer, a fax machine, homeentertainment equipment, a video game console, and/or any type of homeor office computing equipment). Such a portable or fixed computingdevice includes a computing core 26 and one or more interfaces 30, 32,and/or 33. An embodiment of the computing core 26 will be described withreference to FIG. 2.

With respect to the interfaces, each of the interfaces 30, 32, and 33includes software and/or hardware to support one or more communicationlinks via the network 24 and/or directly. For example, interface 30supports a communication link (wired, wireless, direct, via a LAN, viathe network 24, etc.) between the second type of user device 14 and theDS processing unit 16. As another example, DSN interface 32 supports aplurality of communication links via the network 24 between the DSNmemory 22 and the DS processing unit 16, the first type of user device12, and/or the storage integrity processing unit 20. As yet anotherexample, interface 33 supports a communication link between the DSmanaging unit 18 and any one of the other devices and/or units 12, 14,16, 20, and/or 22 via the network 24.

In general, and with respect to data storage, the system 10 supportsthree primary functions: distributed network data storage management,distributed data storage and retrieval, and data storage integrityverification. In accordance with these three primary functions, data canbe distributedly stored in a plurality of physically different locationsand subsequently retrieved in a reliable and secure manner regardless offailures of individual storage devices, failures of network equipment,the duration of storage, the amount of data being stored, attempts athacking the data, etc.

The DS managing unit 18 performs distributed network data storagemanagement functions, which include establishing distributed datastorage parameters, performing network operations, performing networkadministration, and/or performing network maintenance. The DS managingunit 18 establishes the distributed data storage parameters (e.g.,allocation of virtual DSN memory space, distributed storage parameters,security parameters, billing information, user profile information,etc.) for one or more of the user devices 12-14 (e.g., established forindividual devices, established for a user group of devices, establishedfor public access by the user devices, etc.). For example, the DSmanaging unit 18 coordinates the creation of a vault (e.g., a virtualmemory block) within the DSN memory 22 for a user device (for a group ofdevices, or for public access). The DS managing unit 18 also determinesthe distributed data storage parameters for the vault. In particular,the DS managing unit 18 determines a number of slices (e.g., the numberthat a data segment of a data file and/or data block is partitioned intofor distributed storage) and a read threshold value (e.g., the minimumnumber of slices required to reconstruct the data segment).

As another example, the DS managing unit 18 creates and stores, locallyor within the DSN memory 22, user profile information. The user profileinformation includes one or more of authentication information,permissions, and/or the security parameters. The security parameters mayinclude one or more of encryption/decryption scheme, one or moreencryption keys, key generation scheme, and data encoding/decodingscheme.

As yet another example, the DS managing unit 18 creates billinginformation for a particular user, user group, vault access, publicvault access, etc. For instance, the DS managing unit 18 tracks thenumber of times a user accesses a private vault and/or public vaults,which can be used to generate a per-access bill. In another instance,the DS managing unit 18 tracks the amount of data stored and/orretrieved by a user device and/or a user group, which can be used togenerate a per-data-amount bill.

The DS managing unit 18 also performs network operations, networkadministration, and/or network maintenance. As at least part ofperforming the network operations and/or administration, the DS managingunit 18 monitors performance of the devices and/or units of the system10 for potential failures, determines the devices' and/or units'activation status, determines the devices' and/or units' loading, andany other system level operation that affects the performance level ofthe system 10. For example, the DS managing unit 18 receives andaggregates network management alarms, alerts, errors, statusinformation, performance information, and messages from the devices12-14 and/or the units 16, 20, 22. For example, the DS managing unit 18receives a simple network management protocol (SNMP) message regardingthe status of the DS processing unit 16.

The DS managing unit 18 performs the network maintenance by identifyingequipment within the system 10 that needs replacing, upgrading,repairing, and/or expanding. For example, the DS managing unit 18determines that the DSN memory 22 needs more DS units 36 or that one ormore of the DS units 36 needs updating.

The second primary function (i.e., distributed data storage andretrieval) begins and ends with a user device 12-14. For instance, if asecond type of user device 14 has a data file 38 and/or data block 40 tostore in the DSN memory 22, it sends the data file 38 and/or data block40 to the DS processing unit 16 via its interface 30. As will bedescribed in greater detail with reference to FIG. 2, the interface 30functions to mimic a conventional operating system (OS) file systeminterface (e.g., network file system (NFS), flash file system (FFS),disk file system (DFS), file transfer protocol (FTP), web-baseddistributed authoring and versioning (WebDAV), etc.) and/or a blockmemory interface (e.g., small computer system interface (SCSI), internetsmall computer system interface (iSCSI), etc.). In addition, theinterface 30 may attach a user identification code (ID) to the data file38 and/or data block 40.

The DS processing unit 16 receives the data file 38 and/or data block 40via its interface 30 and performs a distributed storage (DS) process 34thereon (e.g., an error coding dispersal storage function). The DSprocessing 34 begins by partitioning the data file 38 and/or data block40 into one or more data segments, which is represented as Y datasegments. For example, the DS processing 34 may partition the data file38 and/or data block 40 into a fixed byte size segment (e.g., 2¹ to2^(n) bytes, where n=>2) or a variable byte size (e.g., change byte sizefrom segment to segment, or from groups of segments to groups ofsegments, etc.).

For each of the Y data segments, the DS processing 34 error encodes(e.g., forward error correction (FEC), information dispersal algorithm,or error correction coding) and slices (or slices then error encodes)the data segment into a plurality of error coded (EC) data slices 42-48,which is represented as X slices per data segment. The number of slices(X) per segment, which corresponds to a number of pillars n, is set inaccordance with the distributed data storage parameters and the errorcoding scheme. For example, if a Reed-Solomon (or other FEC scheme) isused in an n/k system, then a data segment is divided into n slices,where k number of slices is needed to reconstruct the original data(i.e., k is the threshold). As a few specific examples, the n/k factormay be 5/3; 6/4; 8/6; 8/5; 16/10.

For each EC slice 42-48, the DS processing unit 16 creates a uniqueslice name and appends it to the corresponding EC slice 42-48. The slicename includes universal DSN memory addressing routing information (e.g.,virtual memory addresses in the DSN memory 22) and user-specificinformation (e.g., user ID, file name, data block identifier, etc.).

The DS processing unit 16 transmits the plurality of EC slices 42-48 toa plurality of DS units 36 of the DSN memory 22 via the DSN interface 32and the network 24. The DSN interface 32 formats each of the slices fortransmission via the network 24. For example, the DSN interface 32 mayutilize an internet protocol (e.g., TCP/IP, etc.) to packetize the ECslices 42-48 for transmission via the network 24.

The number of DS units 36 receiving the EC slices 42-48 is dependent onthe distributed data storage parameters established by the DS managingunit 18. For example, the DS managing unit 18 may indicate that eachslice is to be stored in a different DS unit 36. As another example, theDS managing unit 18 may indicate that like slice numbers of differentdata segments are to be stored in the same DS unit 36. For example, thefirst slice of each of the data segments is to be stored in a first DSunit 36, the second slice of each of the data segments is to be storedin a second DS unit 36, etc. In this manner, the data is encoded anddistributedly stored at physically diverse locations to improve datastorage integrity and security. Further examples of encoding the datasegments will be provided with reference to one or more of FIGS. 2-12.

Each DS unit 36 that receives an EC slice 42-48 for storage translatesthe virtual DSN memory address of the slice into a local physicaladdress for storage. Accordingly, each DS unit 36 maintains a virtual tophysical memory mapping to assist in the storage and retrieval of data.

The first type of user device 12 performs a similar function to storedata in the DSN memory 22 with the exception that it includes the DSprocessing. As such, the device 12 encodes and slices the data fileand/or data block it has to store. The device then transmits the slices11 to the DSN memory via its DSN interface 32 and the network 24.

For a second type of user device 14 to retrieve a data file or datablock from memory, it issues a read command via its interface 30 to theDS processing unit 16. The DS processing unit 16 performs the DSprocessing 34 to identify the DS units 36 storing the slices of the datafile and/or data block based on the read command. The DS processing unit16 may also communicate with the DS managing unit 18 to verify that theuser device 14 is authorized to access the requested data.

Assuming that the user device is authorized to access the requesteddata, the DS processing unit 16 issues slice read commands to at least athreshold number of the DS units 36 storing the requested data (e.g., toat least 10 DS units for a 16/10 error coding scheme). Each of the DSunits 36 receiving the slice read command, verifies the command,accesses its virtual to physical memory mapping, retrieves the requestedslice, or slices, and transmits it to the DS processing unit 16.

Once the DS processing unit 16 has received a read threshold number ofslices for a data segment, it performs an error decoding function andde-slicing to reconstruct the data segment. When Y number of datasegments has been reconstructed, the DS processing unit 16 provides thedata file 38 and/or data block 40 to the user device 14. Note that thefirst type of user device 12 performs a similar process to retrieve adata file and/or data block.

The storage integrity processing unit 20 performs the third primaryfunction of data storage integrity verification. In general, the storageintegrity processing unit 20 periodically retrieves slices 45, and/orslice names, of a data file or data block of a user device to verifythat one or more slices have not been corrupted or lost (e.g., the DSunit failed). The retrieval process mimics the read process previouslydescribed.

If the storage integrity processing unit 20 determines that one or moreslices is corrupted or lost, it rebuilds the corrupted or lost slice(s)in accordance with the error coding scheme. The storage integrityprocessing unit 20 stores the rebuilt slice, or slices, in theappropriate DS unit(s) 36 in a manner that mimics the write processpreviously described.

FIG. 2 is a schematic block diagram of an embodiment of a computing core26 that includes a processing module 50, a memory controller 52, mainmemory 54, a video graphics processing unit 55, an input/output (IO)controller 56, a peripheral component interconnect (PCI) interface 58,an IO interface 60, at least one IO device interface module 62, a readonly memory (ROM) basic input output system (BIOS) 64, and one or morememory interface modules. The memory interface module(s) includes one ormore of a universal serial bus (USB) interface module 66, a host busadapter (HBA) interface module 68, a network interface module 70, aflash interface module 72, a hard drive interface module 74, and a DSNinterface module 76. Note the DSN interface module 76 and/or the networkinterface module 70 may function as the interface 30 of the user device14 of FIG. 1. Further note that the IO device interface module 62 and/orthe memory interface modules may be collectively or individuallyreferred to as IO ports.

The processing module 50 may be a single processing device or aplurality of processing devices. Such a processing device may be amicroprocessor, micro-controller, digital signal processor,microcomputer, central processing unit, field programmable gate array,programmable logic device, state machine, logic circuitry, analogcircuitry, digital circuitry, and/or any device that manipulates signals(analog and/or digital) based on hard coding of the circuitry and/oroperational instructions. The processing module 50 may have anassociated memory and/or memory element, which may be a single memorydevice, a plurality of memory devices, and/or embedded circuitry of theprocessing module 50. Such a memory device may be a read-only memory,random access memory, volatile memory, non-volatile memory, staticmemory, dynamic memory, flash memory, cache memory, and/or any devicethat stores digital information. Note that if the processing module 50includes more than one processing device, the processing devices may becentrally located (e.g., directly coupled together via a wired and/orwireless bus structure) or may be distributedly located (e.g., cloudcomputing via indirect coupling via a local area network and/or a widearea network). Further note that when the processing module 50implements one or more of its functions via a state machine, analogcircuitry, digital circuitry, and/or logic circuitry, the memory and/ormemory element storing the corresponding operational instructions may beembedded within, or external to, the circuitry comprising the statemachine, analog circuitry, digital circuitry, and/or logic circuitry.Still further note that, the memory element stores, and the processingmodule 50 executes, hard coded and/or operational instructionscorresponding to at least some of the steps and/or functions illustratedin FIGS. 1-19.

FIG. 3 is a schematic block diagram of an embodiment of a dispersedstorage (DS) processing module 34 of user device 12 and/or of the DSprocessing unit 16. The DS processing module 34 includes a gatewaymodule 78, an access module 80, a grid module 82, and a storage module84. The DS processing module 34 may also include an interface 30 and theDSnet interface 32 or the interfaces 68 and/or 70 may be part of userdevice 12 or of the DS processing unit 16. The DS processing module 34may further include a bypass/feedback path between the storage module 84to the gateway module 78. Note that the modules 78-84 of the DSprocessing module 34 may be in a single unit or distributed acrossmultiple units.

In an example of storing data, the gateway module 78 receives anincoming data object that includes a user ID field 86, an object namefield 88, and the data object field 40 and may also receivecorresponding information that includes a process identifier (e.g., aninternal process/application ID), metadata, a file system directory, ablock number, a transaction message, a user device identity (ID), a dataobject identifier, a source name, and/or user information. The gatewaymodule 78 authenticates the user associated with the data object byverifying the user ID 86 with the DS managing unit 18 and/or anotherauthenticating unit.

When the user is authenticated, the gateway module 78 obtains userinformation from the management unit 18, the user device, and/or theother authenticating unit. The user information includes a vaultidentifier, operational parameters, and user attributes (e.g., userdata, billing information, etc.). A vault identifier identifies a vault,which is a virtual memory space that maps to a set of DS storage units36. For example, vault 1 (i.e., user 1's DSN memory space) includeseight DS storage units (X=8 wide) and vault 2 (i.e., user 2's DSN memoryspace) includes sixteen DS storage units (X=16 wide). The operationalparameters may include an error coding algorithm, the width n (number ofpillars X or slices per segment for this vault), a read threshold T, awrite threshold, an encryption algorithm, a slicing parameter, acompression algorithm, an integrity check method, caching settings,parallelism settings, and/or other parameters that may be used to accessthe DSN memory layer.

The gateway module 78 uses the user information to assign a source name35 to the data. For instance, the gateway module 78 determines thesource name 35 of the data object 40 based on the vault identifier andthe data object. For example, the source name may contain a fileidentifier (ID), a vault generation number, a reserved field, and avault identifier (ID). As another example, the gateway module 78 maygenerate the file ID based on a hash function of the data object 40.Note that the gateway module 78 may also perform message conversion,protocol conversion, electrical conversion, optical conversion, accesscontrol, user identification, user information retrieval, trafficmonitoring, statistics generation, configuration, management, and/orsource name determination.

The access module 80 receives the data object 40 and creates a series ofdata segments 1 through Y 90-92 in accordance with a data storageprotocol (e.g., file storage system, a block storage system, and/or anaggregated block storage system). The number of segments Y may be chosenor randomly assigned based on a selected segment size and the size ofthe data object. For example, if the number of segments is chosen to bea fixed number, then the size of the segments varies as a function ofthe size of the data object. For instance, if the data object is animage file of 4,194,304 eight bit bytes (e.g., 33,554,432 bits) and thenumber of segments Y=131,072, then each segment is 256 bits or 32 bytes.As another example, if segment size is fixed, then the number ofsegments Y varies based on the size of data object. For instance, if thedata object is an image file of 4,194,304 bytes and the fixed size ofeach segment is 4,096 bytes, then the number of segments Y=1,024. Notethat each segment is associated with the same source name.

The grid module 82 receives the data segments and may manipulate (e.g.,compression, encryption, cyclic redundancy check (CRC), etc.) each ofthe data segments before performing an error coding function of theerror coding dispersal storage function to produce a pre-manipulateddata segment. After manipulating a data segment, if applicable, the gridmodule 82 error encodes (e.g., Reed-Solomon, Convolution encoding,Trellis encoding, etc.) the data segment or manipulated data segmentinto X error coded data slices 42-44.

The value X, or the number of pillars (e.g., X=16), is chosen as aparameter of the error coding dispersal storage function. Otherparameters of the error coding dispersal function include a readthreshold T, a write threshold W, etc. The read threshold (e.g., T=10,when X=16) corresponds to the minimum number of error-free error codeddata slices required to reconstruct the data segment. In other words,the DS processing module 34 can compensate for X-T (e.g., 16−10=6)missing error coded data slices per data segment. The write threshold Wcorresponds to a minimum number of DS storage units that acknowledgeproper storage of their respective data slices before the DS processingmodule indicates proper storage of the encoded data segment. Note thatthe write threshold is greater than or equal to the read threshold for agiven number of pillars (X).

For each data slice of a data segment, the grid module 82 generates aunique slice name 37 and attaches it thereto. The slice name 37 includesa universal routing information field and a vault specific field and maybe 48 bytes (e.g., 24 bytes for each of the universal routinginformation field and the vault specific field). As illustrated, theuniversal routing information field includes a slice index, a vault ID,a vault generation, and a reserved field. The slice index is based onthe pillar number and the vault ID and, as such, is unique for eachpillar (e.g., slices of the same pillar for the same vault for anysegment will share the same slice index). The vault specific fieldincludes a data name, which includes a file ID and a segment number(e.g., a sequential numbering of data segments 1-Y of a simple dataobject or a data block number).

Prior to outputting the error coded data slices of a data segment, thegrid module may perform post-slice manipulation on the slices. Ifenabled, the manipulation includes slice level compression, encryption,CRC, addressing, tagging, and/or other manipulation to improve theeffectiveness of the computing system.

When the error coded data slices of a data segment are ready to beoutputted, the grid module 82 determines which of the DS storage units36 will store the EC data slices based on a dispersed storage memorymapping associated with the user's vault and/or DS storage unitattributes. The DS storage unit attributes may include availability,self-selection, performance history, link speed, link latency,ownership, available DSN memory, domain, cost, a prioritization scheme,a centralized selection message from another source, a lookup table,data ownership, and/or any other factor to optimize the operation of thecomputing system. Note that the number of DS storage units 36 is equalto or greater than the number of pillars (e.g., X) so that no more thanone error coded data slice of the same data segment is stored on thesame DS storage unit 36. Further note that EC data slices of the samepillar number but of different segments (e.g., EC data slice 1 of datasegment 1 and EC data slice 1 of data segment 2) may be stored on thesame or different DS storage units 36.

The storage module 84 performs an integrity check on the outboundencoded data slices and, when successful, identifies a plurality of DSstorage units based on information provided by the grid module 82. Thestorage module 84 then outputs the encoded data slices 1 through X ofeach segment 1 through Y to the DS storage units 36. Each of the DSstorage units 36 stores its EC data slice(s) and maintains a localvirtual DSN address to physical location table to convert the virtualDSN address of the EC data slice(s) into physical storage addresses.

In an example of a read operation, the user device 12 and/or 14 sends aread request to the DS processing unit 16, which authenticates therequest. When the request is authentic, the DS processing unit 16 sendsa read message to each of the DS storage units 36 storing slices of thedata object being read. The slices are received via the DSnet interface32 and processed by the storage module 84, which performs a parity checkand provides the slices to the grid module 82 when the parity check wassuccessful. The grid module 82 decodes the slices in accordance with theerror coding dispersal storage function to reconstruct the data segment.The access module 80 reconstructs the data object from the data segmentsand the gateway module 78 formats the data object for transmission tothe user device.

FIG. 4 is a schematic block diagram of an embodiment of a grid module 82that includes a control unit 73, a pre-slice manipulator 75, an encoder77, a slicer 79, a post-slice manipulator 81, a pre-slice de-manipulator83, a decoder 85, a de-slicer 87, and/or a post-slice de-manipulator 89.Note that the control unit 73 may be partially or completely external tothe grid module 82. For example, the control unit 73 may be part of thecomputing core at a remote location, part of a user device, part of theDS managing unit 18, or distributed amongst one or more DS storageunits.

In an example of a write operation, the pre-slice manipulator 75receives a data segment 90-92 and a write instruction from an authorizeduser device. The pre-slice manipulator 75 determines if pre-manipulationof the data segment 90-92 is required and, if so, what type. Thepre-slice manipulator 75 may make the determination independently orbased on instructions from the control unit 73, where the determinationis based on a computing system-wide predetermination, a table lookup,vault parameters associated with the user identification, the type ofdata, security requirements, available DSN memory, performancerequirements, and/or other metadata.

Once a positive determination is made, the pre-slice manipulator 75manipulates the data segment 90-92 in accordance with the type ofmanipulation. For example, the type of manipulation may be compression(e.g., Lempel-Ziv-Welch, Huffman, Golomb, fractal, wavelet, etc.),signatures (e.g., Digital Signature Algorithm (DSA), Elliptic Curve DSA,Secure Hash Algorithm, etc.), watermarking, tagging, encryption (e.g.,Data Encryption Standard, Advanced Encryption Standard, etc.), addingmetadata (e.g., time/date stamping, user information, file type, etc.),cyclic redundancy check (e.g., CRC32), and/or other data manipulationsto produce the pre-manipulated data segment.

The encoder 77 encodes the pre-manipulated data segment 92 using aforward error correction (FEC) encoder (and/or other type of erasurecoding and/or error coding) to produce an encoded data segment 94. Theencoder 77 determines which forward error correction algorithm to usebased on a predetermination associated with the user's vault, a timebased algorithm, user direction, DS managing unit direction, controlunit direction, as a function of the data type, as a function of thedata segment 92 metadata, and/or any other factor to determine algorithmtype. The forward error correction algorithm may be Golay,Multidimensional parity, Reed-Solomon, Hamming, Bose Ray ChauduriHocquenghem (BCH), Cauchy-Reed-Solomon, or any other FEC encoder. Notethat the encoder 77 may use a different encoding algorithm for each datasegment 92, the same encoding algorithm for the data segments 92 of adata object, or a combination thereof.

The encoded data segment 94 is of greater size than the data segment 92by the overhead rate of the encoding algorithm by a factor of X/T, whereX is the width or number of slices, and T is the read threshold. In thisregard, the corresponding decoding process can accommodate at most X-Tmissing EC data slices and still recreate the data segment 92. Forexample, if X=16 and T=10, then the data segment 92 will be recoverableas long as 10 or more EC data slices per segment are not corrupted.

The slicer 79 transforms the encoded data segment 94 into EC data slicesin accordance with the slicing parameter from the vault for this userand/or data segment 92. For example, if the slicing parameter is X=16,then the slicer 79 slices each encoded data segment 94 into 16 encodedslices.

The post-slice manipulator 81 performs, if enabled, post-manipulation onthe encoded slices to produce the EC data slices. If enabled, thepost-slice manipulator 81 determines the type of post-manipulation,which may be based on a computing system-wide predetermination,parameters in the vault for this user, a table lookup, the useridentification, the type of data, security requirements, available DSNmemory, performance requirements, control unit directed, and/or othermetadata. Note that the type of post-slice manipulation may includeslice level compression, signatures, encryption, CRC, addressing,watermarking, tagging, adding metadata, and/or other manipulation toimprove the effectiveness of the computing system.

In an example of a read operation, the post-slice de-manipulator 89receives at least a read threshold number of EC data slices and performsthe inverse function of the post-slice manipulator 81 to produce aplurality of encoded slices. The de-slicer 87 de-slices the encodedslices to produce an encoded data segment 94. The decoder 85 performsthe inverse function of the encoder 77 to recapture the data segment90-92. The pre-slice de-manipulator 83 performs the inverse function ofthe pre-slice manipulator 75 to recapture the data segment 90-92.

FIG. 5 is a diagram of an example of slicing an encoded data segment 94by the slicer 79. In this example, the encoded data segment 94 includesthirty-two bits, but may include more or less bits. The slicer 79disperses the bits of the encoded data segment 94 across the EC dataslices in a pattern as shown. As such, each EC data slice does notinclude consecutive bits of the data segment 94 reducing the impact ofconsecutive bit failures on data recovery. For example, if EC data slice2 (which includes bits 1, 5, 9, 13, 17, 21, 25, and 29) is unavailable(e.g., lost, inaccessible, or corrupted), the data segment can bereconstructed from the other EC data slices (e.g., 1, 3 and 4 for a readthreshold of 3 and a width of 4).

FIG. 6 is a schematic block diagram of an embodiment of a post-slicede-manipulator 102. As illustrated, post-slice de-manipulator 102includes a plurality of hash function generators 120, a multiplexer 122(MUX), and a plurality of pillar outputs 1-8. In an example operation,the plurality of hash functions 120 receive data elements 1-7 from atleast one of a user device 12-14, a DS managing unit 18, a DS processingunit 16, a storage integrity processing unit 20, and a DSN memory 22.Data elements 1-7, which may be of a variable length, includes text,speech, audio, video, and/or graphics. For example, data elements 1-7may include one or more of a name, a social security number, a date ofbirth, an address, a city of birth, a passport number, and a biometric.Such a biometric may include one or more of a fingerprint, a retinalscan, a DNA profile, and a blood type.

The plurality of hash functions 120 calculates hashes (e.g., secure hashalgorithm, SHA-1) of the corresponding data elements 1-7. Note that thehash functions 120 may truncate the result to a common size. The MUX 122selects any of the hash calculations to create a plurality of pillarslices 118. In an example, each pillar may be a unique hash output or arepeat of another pillar. For example, the MUX 122 creates pillar 1 fromdata element 1, pillar 2 from data element 2, pillar 3 from data element3, pillar 4 from data element 4, pillar 5 from data element 5, pillar 6from data element 6, pillar 7 from data element 7, and pillar 8 fromdata element 7. Note that repeated pillars may give more weight to thedata element. For example, the biometric retinal scan may be given moreweight since it is harder to duplicate than the name. In anotherexample, the MUX 122 skips pillars by not populating the pillar with thehash calculation of a data element. A method to determine a pillarpopulation scheme is discussed in greater detail with reference to FIG.7.

The post-slice de-manipulator 102 sends the slices 118 to a DSprocessing. The DS processing receives the slices 118 and decodes theslices 118 in accordance with an error code in dispersal storagefunction to produce an access ID. Note that each combination of a readthreshold number of pillars may produce a unique access ID for the samerecord. For instance, the DS processing may access the patient recordsby providing a sufficient number of data elements to populate a readthreshold number of pillars. In such an instance, each of the access IDsmay be an alias to a same record ID. The record ID may be an object nameof the patient records or a DSN address (e.g., source name) of thepatient records. The connection of access IDs to the record ID isdiscussed in greater detail with reference to FIG. 8.

In another example, the access ID represents an object name of recordsor a DSN address of records. In an instance, the pillar width n=8 andthe read threshold is 5. Note that there are 56 combinations ofproviding 5 data element hashes as 5 pillars of 8 pillars. The MUX 122populates pillar 1 with the hash of the name, pillar 2 with the hash ofthe social security number, pillar 3 with the hash of the data of birth,and pillars 4 and 5 with the hash of the biometric retinal scan. In theinstance, MUX 122 does not populate pillars 7 and 8. The DS processingde-slices and decodes pillars 1-5 to produce access ID 1. The DSprocessing determines the record ID 1 utilizing the access ID 1 in atable lookup. The DS processing retrieves the slices for the recordutilizing the record ID 1 as the object name.

Note that the Personal information data elements are not stored in theDSN memory thus providing a security improvement regarding de-slicingand decoding of a plurality of data elements. The resulting decoded datasegment may be utilized as an access ID to records associated with thedata elements. For example, the data elements may include descriptors ofa medical patient (e.g., name, date of birth etc). Access may beprovided to full patient medical records based on providing a thresholdnumber of the data elements. For example, providing at least 5 (e.g.,any 5) of a possible list of 7 items enables access to the patientrecords.

FIG. 7 is a flowchart illustrating an example of determining slices. Themethod begins with step 124 where a dispersed storage (DS) processing(e.g., a processing module of a DS processing module) receives dataelements from at least one of a user device, the DS managing unit, a DSprocessing unit, a storage integrity processing unit, and a DSN memory.Data elements may comprise text, speech, audio, video, and may vary inlength. Note that all of the data elements are required initially tocreate the access ID entries in the table. The data elements may includea data element type indicator to signify what type of information it is(e.g., name, date of birth, etc.).

At step 126, the DS processing calculates a hash of each of the dataelements. The DS processing may truncate the hash to reduce the sizesuch that it is compatible with a standard slice size and/or access IDsize. At step 128, the DS processing determines operational parameters(e.g., error coding dispersal storage function parameters) where theoperational parameters may include one or more of pillar width, readthreshold, pillar ordering by data element type, de-slicing method,decoding method, decryption method, and a decryption key. Such adetermination may be based on one or more of a data element typeindicator, a data element, a vault lookup, a predetermination, and acommand.

At step 130, the DS processing determines a MUX scheme where the MUXscheme may include ordering of pillars by data element type and whichpillars may be replicated. Such a determination may be based on one ormore of the operational parameters, the data element type indicator, adata element, a vault lookup, a predetermination, and a command. At step132, the DS processing performs a MUX operation on the data elementhashes in accordance with the MUX scheme to produce pillar slices. Notethat some pillars may be filled one for one, some may be skipped, andsome may be replicated. At step 134, the DS processing de-slices anddecodes the pillar slices in accordance with the operational parametersto produce an access ID. In instance, the DS processing subsequentlydetermines a record ID based on the access ID. Next, the DS processingretrieves records based on the record ID.

FIG. 8 is a table illustrating an example of an access-ID-to-record-IDtable 136. As illustrated, the access-ID-to-record-ID table 136 includesan access ID field and a record ID field. In an example, the record IDis a data object name of a data object stored in a dispersed storagenetwork (DSN) memory. In another example, the record ID is a DSN address(e.g., source name and/or slice names) of where the record is stored inthe DSN memory. The access ID is produced based on a plurality of dataelements. Note that all of the data elements are required initially tocreate the access ID entries in the table. A record ID may have aplurality of associated access IDs where each of the plurality of accessIDs corresponds to a different unique combination of data elements thatproduce the access ID. As illustrated, access ID 1_1 through 1_56 areassociated with record ID 1 and access ID 2_1 through 2_56 areassociated with record ID 2.

A DS processing may establish the association between access ID andrecord ID. For example, the DS processing utilizes each read thresholdcombination of pillar slices (e.g., in accordance with the valid MUXscheme) to decode and produce a plurality of access IDs. The DSprocessing enters each access ID into the access ID field of the table.The DS processing determines an associated record ID based on or more ofa random name, a predetermination, a lookup, and a command. The DSprocessing enters the record ID in the record ID field adjacent to theplurality of corresponding access IDs. The DS processing stores thetable in local memory and/or as slices, produced utilizing an errorcoding dispersal storage function, in the DSN memory.

The DS processing may subsequently retrieve the record ID by utilizing asufficient number of data elements to produce a read threshold ofpillars to decode any one of the access IDs (e.g., as an index to theassociated record ID in the table). The DS processing may access therecord based on the record ID (e.g., to initially populate the recordswith patient medical records, to retrieve the patient medical records).

FIG. 9 is another schematic block diagram of another embodiment of acomputing system. As illustrated, the system includes a plurality ofuser devices 1-5 and a DSN memory 22. As illustrated, user device 1includes an encryptor 138, a plurality of encryptors 139, a profile 140,a key 142, a DS processing 34, and a transform function 144. Asillustrated, user devices 2-4 include the DS processing 34, a decryptor148, a profile 141, a decryptor 150, and a transform cache 146. Asillustrated, user device 5 includes the DS processing 34, the decryptor148, the profile 141, the decryptor 150, and a de-transform function152. The profile 140 may include social networking content such as name,personal information, pictures, video clips, message board information,links, contacts, etc. The key 142 may be an entered managed encryptionkey or a random encryption key (e.g., based on a random numbergenerator).

In an example of operation, the encryptor 138 of a profile owner (e.g.,user device 1) encrypts the profile 140 utilizing the key 142 to producean encrypted profile. The DS processing 34 encodes the encrypted profileutilizing an error coding dispersal storage function to produce slices11. The DS processing 34 of user device 1 stores the slices 11 of theprofile 140 in the DSN memory 22.

A processing module of user device 1 determines direct contacts to sendan encrypted key to based on one or more of a list of direct contacts, acommand, a polling of contacts, a message board, a profile entry, and aDSN user vault lookup. For example, the processing module determines tosend the encrypted key to user devices 2-4 based on a list of directcontacts associated with user device 1. Next, the plurality ofencryptors 139 encrypts the key 142 in accordance with the operationalparameters (e.g., utilizing the unique public key 2-4 of each of thedirect contact targets such as user devices 2-4). For example, the firstencryptor 139 encrypts the key 142 utilizing public key 2 and sends theencrypted key to user device 2 since user device 2 was determined to bea direct contact. In an instance, the encryptor 139 appends a portion(e.g., DSN address of the profile, etc.) of the operational parametersto the encrypted key before sending the encrypted key to a directcontact user device. In another instance, the encryptor 139 appends aportion (e.g., DSN address of the profile, etc.) of the operationalparameters to the key, and encrypts both before sending the encryptedkey to a direct contact user device. The method repeats for eachtargeted direct contact user device.

In the example of operation, the transform function 144 transforms thekey 142 into a plurality of shared secret transforms 1-3 (e.g., Shamirsecret shares or encoded data slices) in accordance with the operationalparameters (e.g., number of unique transforms, threshold number) suchthat subsequent recovery of a threshold number of transforms willreproduce the key 142. For example, the transform function 144 maycreate transforms 1-3 based on the key 142 in accordance with theoperational parameters (e.g., transforms=3, threshold=2). Note thatrecovery of any two of the three transforms may enable reproducing thekey 142. Note that any number of transforms may be created with athreshold that is equal to or less than the number of transforms. In aninstance, any number of direct contacts and any number of desired directcontacts to enable a secondary contact to access the profile ownerprofile may be established.

In another example of generating transforms, the transform function 144transforms the key 142 into a plurality of encoded data slices inaccordance with the operational parameters (e.g., pillar width n, readthreshold k) such that subsequent recovery of a read threshold number ofslices can be de-sliced and decoded to reproduce the key 142. In aninstance, the transform function 144 creates transforms 1-3 (e.g.,pillars 1-3) based on the key 142 in accordance with the operationalparameters (e.g., n=3, k=2). Recovery of any two of the three transforms(e.g., encoded data slices) enables reproducing the key 142. Note thatany number of transforms may be created with a threshold that is equalto or less than the number of transforms. In an instance, any number ofdirect contacts and any number of desired direct contacts to enable asecondary contact to access the profile owner profile may beestablished.

The transform function 144 may append a portion (e.g., transformthreshold, DSN address of the profile, etc.) of the operationalparameters to the transform before sending the transform to a directcontact user device 2-4. Note that the operational parameters mayinclude a policy that may specify limitations (e.g., who may send, whomay not send, disallowed targets, etc.) on which direct contacts areallowed to forward transformations to candidate secondary contacts.

In an example of operation, the decryptor 150 of user devices 2-4receives the encrypted key from the profile owner user device 1 anddecrypts the encrypted key utilizing a unique private key 2-4 for thecorresponding user device 2-4. For example, user device 3 decrypts theencrypted key utilizing private key 3 to produce the key 142 and/or aportion of operational parameters corresponding to the profile 140. TheDS processing 34 of user devices 2-4 determines DSN memory location ofthe profile encoded data slices 11 based on one or more of theoperational parameters, a message from the profile owner, a command, aDSN lookup, a message board listing, and a predetermination. The DSprocessing 34 retrieves the slices 11 from the DSN memory 22 andde-slices and decodes the slices 11 in accordance with the operationalparameters to produce the encrypted profile. The decryptor 148 decryptsthe encrypted profile in accordance with the operational parameters(e.g., decryption algorithm information) utilizing the key 142 toproduce the profile 141 which may be cached in a profile buffer.

In an example of operation, the direct contact (e.g., user device 2-4)may receive a transform 1-3 from the transform function 144 of userdevice 1. The user device 2-4 saves the transform 1-3 in the transformcache 146. The direct contact user devices 2-4 determines to send thetransform 1-3 from the transform cache 146 to another user device (e.g.,user device 5) that may become a secondary contact. A relationship mayexist between one or more of the direct contacts and the secondarycontact. The profile owner may enable one or more of their directcontacts to help a secondary contact gain access to the profile ownerprofile. In an instance, the secondary user device is a friend of afriend of the profile owner user device. Such a determination may bebased on one or more of a user input, a policy, a list, a command, atimer, a list comparison, a request, a DSN vault lookup, and apredetermination. The user device 2-4 sends the transform 1-3 from thetransform cache 146 to another user device 5 that may become a secondarycontact.

The secondary contact (e.g., user device 5) DS processing 34 determinesthe DSN memory 22 location of the profile encoded data slices 11 basedon one or more of the operational parameters, a message from one or moreof the direct contacts, a command, a DSN lookup, a message boardlisting, and a predetermination. The DS processing 34 retrieves theprofile encoded slices 11 from the DSN memory 22 and decodes the slicesin accordance with the operational parameters to produce the encryptedprofile. The de-transform function 152 of user device 5 receives atleast a threshold number of transform functions from the other userdevices 2-4 and de-transforms the transforms 1-3 to produce the key 142.Note that the transform may include a Shamir shared secret approach ormay utilize DS processing and encoded data slices. Either approachutilizes a threshold number of secrets or slices to recreate theoriginal information (e.g., the key 142 to decrypt the profile 140).Note that there may be tens, hundreds, thousands, or more of secondarycontacts. The decryptor 148 decrypts the encrypted profile in accordancewith the operational parameters (e.g., decryption algorithm information)utilizing the key 142 to produce the profile 141 which may be cached ina profile buffer.

Note that the computing system enables a first user device to share asocial networking profile with a first set of other user devices bysending profile access information to each user device of the first setof user devices. A second set of user devices may access the profilewhen a threshold number of user devices of the first set of user devicessend one of the second set of user devices profile access information.For example, direct contacts of the first user device may access thefirst user device social networking profile and secondary contacts mayaccess the first user device profile when at least some of the directcontacts enable the secondary contact to access the first user devicesocial networking profile. The first user device securely stores thefirst user device social networking profile in DSN memory to provideimproved confidentiality such that the DSN memory provider may notaccess the profile unless authorized by the first user device.

FIG. 10 is another schematic block diagram of another embodiment of acomputing system. As illustrated, the system includes a user device A(e.g., sourcing data to store), a plurality of user devices 1-3, and adispersed storage network (DSN) memory 22. Note that the plurality ofuser devices 1-3 may include tens, hundreds, thousands, or more of userdevices. As illustrated, user device A includes data 154, an encryptor158, a DS processing A, a key 156, and a DS processing B. Alternatively,the user device A DS processing A and DS processing B are implemented inthe same DS processing. As illustrated, user devices 1-3 include a keyslice cache 1-3, a DS processing A, a DS processing B, a decryptor 160,and data 154. Alternatively, the user devices 1-3 DS processing A and DSprocessing B are implemented in the same DS processing. The key slicecache 1-3 may be implemented with memory to store encoded key slices(e.g., a removable memory stick, a magnetic disk drive memory, etc.).The data 154 may include any type of digital information including oneor more of text, pictures, video clips, records, database information,message board information, links, contacts, etc. The key 156 may be anentered managed key or a random key (e.g., an encryption key producedbased on a random number).

In an example of a storage operation, the processing module of userdevice A obtains a key 156. For example, processing module obtains thekey 156 from a memory lookup. In another example, the processing moduleobtains the key 156 from an output of a random number generator. The DSprocessing B of user device A encodes the key 156 utilizing a firsterror coding dispersal storage function to produce a set of encoded keyslices. Alternatively, the DS processing B of user device A transformsthe key 156 utilizing a shared secret transformation function to producethe set of encoded key slices wherein a threshold number of set ofencoded key slices are required to reproduce the key 156. In aninstance, the DS processing B of user device A transforms the key 156utilizing a Shamir shared secret transformation function.

The DS processing B outputs the set of encoded key slices by performingat least one of storing at least one encoded key slice of the set ofencoded key slices in a local memory of a user device (e.g., user deviceA) and outputting at least one other encoded key slice of the set ofencoded key slices to a second user device (e.g. user devices 1-3) forstorage therein, and outputting the set of encoded key slices to aplurality of user devices (e.g. user devices 1-3) for storage therein.The DS processing B determines which of the plurality of user devices1-3 to send the encoded key slices based on one or more of error codingdispersal storage function parameters, a list of the other user devices,a command, a query of available user devices, a message board, a profileentry, and a DSN user vault lookup. For example, a processing module ofDS processing B may determine to send the encoded key slices to each ofuser devices 1-3 based on a poll of active user devices. In an instance,the query may reveal that key slice cache 2 of user device 2 isavailable to accept an encoded key slice of the encoded key slices. Theencryptor 158 encrypts a portion of data 154 utilizing the key 156 inaccordance with an encryption function to produce an encrypted portionof data.

The DS processing A of user device A encodes the encrypted portion ofdata utilizing a second error coding dispersal storage function toproduce a set of encoded data slices. In an instance, the first errorcoding dispersal storage function is substantially equal to the seconderror coding dispersal storage function. In another instance, the firsterror coding dispersal storage function is substantially not equal tothe second error coding dispersal storage function. The DS processing Aof user device A outputs the set of encoded data slices by at least oneof outputting the set of encoded data slices to the DSN memory forstorage therein and outputting the set of encoded data slices to aplurality of user devices (e.g., user devices 1-3) for storage therein.In addition, the DS processing B of user device A may encode theencryption function (e.g., software of an encryption and/or decryptionalgorithm) using the first or second error coding dispersal storagefunction to produce a set of encoded encryption function slices andoutput the set of encoded encryption function slices to the plurality ofuser devices (e.g., user devices 1-3) for storage therein. Note that thekey and encryption function does not exist in the DSN memory 22 thusproviding improved data confidentiality (e.g., not even a DSN memoryprovider can access the data).

In an example of a retrieval operation, the DS processing B of userdevice 1 obtains encoded key slices from the plurality of user devices1-3. The DS processing B obtains the encoded key slices by at least oneof retrieving an encoded key slice of the encoded key slices from alocal memory (e.g., key slice cache 1) of a user device (e.g., userdevice 1) of the plurality of user devices along with retrieving otherencoded key slices of the encoded key slices from other user devices(e.g., user devices 2-3) of the plurality of user devices and receivingthe encoded key slices from the other user devices of the plurality ofuser devices. In an instance, DS processing B of user device 1 sends anencoded key slice retrieval request to user devices 2-3 and receivesencoded key slices in response to the request. In another instance, DSprocessing B of user device 1 reads the encoded data slices directlyfrom key slice caches 2-3 when key slice caches 2-3 are directlyaccessible to the DS processing B (e.g., via an electrical interface,via a memory stick interface, etc.). The DS processing B of user device1 decodes the threshold number of the encoded key slices utilizing afirst error coding dispersal storage function to produce a key 156 whena threshold number of the encoded key slices have been obtained. The DSprocessing A user device 1 sends an encoded data slice retrieval requestto the DSN memory 22 and/or to user devices 2-3. The request may includeone or more of a slice name, a user device ID, and an authenticationtoken.

In an instance, the authentication token includes the key 156. The DSprocessing A user device 1 receives encoded data slices by at least oneof receiving the encoded data slices from the DSN memory 22 in responseto the request and receiving the encoded data slices from the pluralityof user devices 1-3 in response to a user device request. The DSprocessing B of user device 1 decodes the threshold number of encodeddata slices utilizing a second error coding dispersal storage functionto produce encrypted data when a threshold number of the encoded dataslices have been received. In an instance, the first error codingdispersal storage function is substantially equal to the second errorcoding dispersal storage function. In another instance, the first errorcoding dispersal storage function is substantially not equal to thesecond error coding dispersal storage function. The decryptor 160 ofuser device 1 decrypts the encrypted data utilizing the key 156 and anencryption function to produce data 154. In addition, the DS processingB may obtain encoded encryption function slices and decode the encodedencryption function slices in accordance with the first or second errorcoding dispersal storage function to produce the encryption function(e.g., software of an encryption and/or decryption algorithm) when athreshold number of encoded encryption function slices have beenobtained.

FIG. 11 is a flow chart illustrating an example of encrypting andstoring of encoded data slices. The method begins with step 162 where adispersed storage (DS) processing (e.g. a processing module of a DSprocessing module) receives a store request and a data object to storefrom the user device or other unit of the system. The request mayinclude a command, a user ID, a data object name, a data type, a datasize, a priority indicator, a security indicator, a performanceindicator, and/or other metadata pertaining to the data object.

At step 164, the DS processing determines operational parameters (e.g.,including the encryption scheme) based on one or more of vaultinformation, a predetermination, a command, a user ID, a data objectname, a data type, a data size, a priority indicator, a securityindicator, a performance indicator, and other metadata. For example, theDS processing may determine to utilize advanced encryption standard(e.g., AES-256) based on the data type indicating a sensitive video fileand a relatively high security indicator.

At step 166, the DS processing encrypts the data object to produce anencrypted data object in accordance with the operational parameters. TheDS processing determines data segment size based in part on theoperational requirements with an emphasis on the security aspects. Forexample, the DS processing may determine to use more and smaller datasegments when the security indicator indicates a higher desired level ofsecurity. At step 168, the DS processing creates data segments from theencrypted data object in accordance with the operational parameters andthe determined data segment size.

At step 170, the DS processing creates an encoded data segment from eachdata segment in accordance with the operational parameters (e.g., theencoding algorithm). Note that the coding algorithm determination may bebased in part on the security requirements. For example, a strongerencoding algorithm (e.g., to provide better error correction forencrypted data) may be determined when the security indicator indicatesthat a higher level of security is required. At step 172, the DSprocessing unit creates EC data slices of each pillar for each datasegment in accordance with the operational parameters. At step 174, theDS processing determines a virtual DSN address for the slices (e.g.,source name and/or slice names) and appends the virtual DSN address tothe slices to enable subsequent identification of the slices.

At step 176, the DS processing encrypts at least a portion of the sliceand/or appended DSN address information in accordance with theoperational parameters (e.g., encryption algorithm, key) to produce incricket slices. In an instance, the DS processing encrypts bothtogether. In another instance, the DS processing encrypts the sliceportion but not the DSN address portion. Note that slices may share thesame encryption key or use different encryption keys.

At step 178, the DS processing unit determines where (e.g., whichphysical DS units) to store the slices in the DSN memory based on one ormore of the virtual DSN address, a virtual DSN address to physicallocation table lookup, the operational parameters, vault information, apredetermination, a command, the user ID, the data object name, the datatype, the data size, the priority indicator, the security indicator, theperformance indicator, and the other metadata. For example, the DSprocessing may determine to utilize DS units in a storage set for thevault that are in a more secure environment when the security indicatorindicates that a higher level of security is required. The DS processingunit sends the encrypted slices to the DSN memory with a store commandin accordance with the operational parameters (e.g., a write threshold,DSN memory locations) for storage therein.

FIG. 12 is a flowchart illustrating an example of retrieving anddecrypting encoded data slices. The method begins at step 180 where adispersed storage (DS) processing receives a retrieval request and adata object name to retrieve from a requester (e.g., a user device orother unit of the system). The request may include a command, a user ID,a data object name, a data type, a data size, a priority indicator, asecurity indicator, a performance indicator, and/or other metadatapertaining to the data object.

At step 182, the DS processing determines operational parameters (e.g.,including the encryption scheme) based on one or more of vaultinformation, a predetermination, a command, the user ID, the data objectname, the data type, the data size, the priority indicator, the securityindicator, the performance indicator, and the other metadata. Forexample, the DS processing determines to utilize advanced encryptionstandard (e.g., AES-256) based on the data type indicating a sensitivevideo file and a relatively high security indicator.

At step 184, the DS processing determines where (e.g., which physical DSunits) to retrieve slices from a dispersed storage network (DSN) memorybased on one or more of a virtual DSN address, a virtual DSN address tophysical location table lookup, the operational parameters, vaultinformation, a predetermination, a command, the user ID, the data objectname, the data type, the data size, the priority indicator, the securityindicator, the performance indicator, and the other metadata. The DSprocessing sends a retrieve slice command to the determined DSN units ofthe DSN memory with the slice names and retrieve request in accordancewith the operational parameters (e.g., a read threshold, DSN memorylocations). The DS units send the slices and/or appended DSN addressinformation to the DS processing in response to the request.

At step 186, the DS processing decrypts at least a portion of thereceived (encrypted) slices and/or appended DSN address information inaccordance with the operational parameters (e.g., decryption algorithm,key). In an instance, the DS processing decrypts both together. Inanother instance, the DS processing decrypts the slice portion but notthe DSN address portion. Note that slices may share the same encryptionkey or use different encryption keys.

At step 188, the DS processing de-slices the received EC data slices ofeach pillar for each data segment in accordance with the operationalparameters to produce a plurality of encoded data segments. The DSprocessing may de-append (parse) the virtual DSN address from the slices(e.g., source name and/or slice names). In an example, the DS processingmay compare the received DSN address to the sent DSN address. The DSprocessing may validate the slices when the comparison is favorable(e.g., the same).

At step 190, the DS processing decodes a data segment from the pluralityof received encoded data segments in accordance with the operationalparameters (e.g., the decoding algorithm) to produce a plurality of datasegments. Note that the decoding algorithm determination may be based inpart on the security requirements. For example, a stronger encodingalgorithm (e.g., to provide better error correction for encrypted data)may have been used when the security indicator indicates that a higherlevel of security is required.

At step 192, the DS processing aggregates the plurality of data segmentsto produce an encrypted data object. At step 194, the DS processingdecrypts the encrypted data object in accordance with the operationalparameters to produce the data object. At step 186, the DS processingsends the data object to the requester.

FIG. 13 is another flowchart illustrating another example of encryptingand storing of encoded data slices. The method begins with step 198where a dispersed storage (DS) processing (e.g., a processing module ofa DS processing module) receives a store request and a data object tostore from a requester (e.g., a user device or other unit of thesystem). The request may include a command, a user ID, a data objectname, a data type, a data size, a priority indicator, a securityindicator, a performance indicator, and/or other metadata pertaining tothe data object.

At step 200, the DS processing determines operational parameters (e.g.,error coding dispersal storage function parameters) based on one or moreof vault information, a predetermination, a command, a user ID, a dataobject name, a data type, a data size, a priority indicator, a securityindicator, a performance indicator, and other metadata. Note that theoperational parameters may include encryption configuration information.For example, the DS processing determines the operational parameters toinclude the utilization of an advanced encryption standard (e.g.,AES-256) based on a data type indicating a sensitive video file and arelatively high security indicator.

At step 202, the DS processing encrypts the data object in accordancewith the operational parameters to produce an encrypted data object. Atstep 204, the DS processing determines a data segment size based in parton the operational parameters with an emphasis on security aspects. Forexample, the DS processing may determine to use more and smaller datasegments when the security indicator indicates a higher desired level ofsecurity. The DS processing creates a plurality of data segments fromthe encrypted data object in accordance with the operational parametersand the determined data segment size.

At step 206, the DS processing creates a plurality of encoded datasegments in accordance with the operational parameters (e.g., theencoding algorithm) from the plurality of data segments. Note that thecoding algorithm determination may be based in part on the securityrequirements. For example, the DS processing may utilize a strongerencoding algorithm (e.g., to provide better error correction forencrypted data) when the security indicator indicates that a higherlevel of security is required.

At step 208 DS processing encrypts each encoded data segment of theplurality of encoded data segments in accordance with the operationalparameters to produce a plurality of encrypted data segments. Note thatthe DS processing may encrypt each segment with a different encryptionalgorithm and/or different key to provide improved security. At step210, the DS processing encodes each encrypted data segment of theplurality of encrypted data segments in accordance with the operationalparameters to produce a plurality of sets of encoded data slices. Atstep 212, the DS processing determines a virtual DSN addresscorresponding to each of the slices (e.g., source name and/or slicenames) and appends them to the plurality of sets of encoded data slicesto enable subsequent identification of the slices.

At step 214, the DS processing encrypts at least a portion of the sliceand/or appended DSN address information in accordance with theoperational parameters (e.g., encryption algorithm, key) to produce aplurality of sets of encrypted encoded data slices. In an instance, theDS processing encrypts both together. In another instance, the DSprocessing encrypts the slice portion but not the DSN address portion.Note that slices may share the same encryption key or use differentencryption keys.

At step 216, the DS processing determines where (e.g., which physical DSunits) to store the slices in the DSN memory based on one or more of thevirtual DSN address, a virtual DSN address to physical location tablelookup, the operational parameters, vault information, apredetermination, a command, the user ID, the data object name, the datatype, the data size, the priority indicator, the security indicator, theperformance indicator, and the other metadata. For example, the DSprocessing may determine to utilize DS units in a storage set for thevault that are in a more secure environment when the security indicatorindicates that a higher level of security is required. At step 216, theDS processing sends the plurality of sets of encrypted encoded dataslices to the DSN memory with a store command in accordance with theoperational parameters (e.g., a write threshold, DSN memory locations)for storage therein.

FIG. 14 is another flowchart illustrating another example of retrievingand decrypting encoded data slices. The method begins with step 218where a dispersed storage (DS) processing (e.g., a processing module ofa DS processing module) receives a retrieval request message from arequester (e.g., a user device or other unit of the system). Theretrieval request message may include a command, a read request, a userID, a data object name, a data type, a data size, a priority indicator,a security indicator, a performance indicator, and/or other metadatapertaining to the data object. At step 220, the DS processing determinesoperational parameters (e.g., including the encryption scheme) based onone or more of vault information, a predetermination, a command, theuser ID, the data object name, the data type, the data size, thepriority indicator, the security indicator, the performance indicator,and/or the other metadata. For example, the DS processing determines toutilize advanced encryption standard (e.g., AES-256) based on the datatype indicating a sensitive video file and a relatively high securityindicator.

At step 222, the DS processing determines DS units to retrieve theslices from in a dispersed storage network (DSN) memory based on one ormore of a virtual DSN address, a virtual DSN address to physicallocation table lookup, the operational parameters, vault information, apredetermination, a command, the user ID, the data object name, the datatype, the data size, the priority indicator, the security indicator, theperformance indicator, and the other metadata. At step 222, the DSprocessing sends a retrieve slice request to the DS units with slicenames in accordance with the operational parameters (e.g., a readthreshold, DSN memory locations). The DS units send encoded data slicesand/or appended DSN address information to the DS processing.

At step 224, the DS processing decrypts at least a portion of received(encrypted) slices and/or appended DSN address information in accordancewith the operational parameters (e.g., decryption algorithm, key) toproduce a plurality of sets of slices. In an instance, the DS processingdecrypts both together. In another instance, the DS processing decryptsthe slice portion but not the DSN address portion. Note that slices mayshare the same encryption key or use different encryption keys.

At step 226, the DS processing decodes an encoded data slice set of theplurality of sets of slices (e.g., for each data segment) in accordancewith the operational parameters to produce an encrypted data segment.The method repeats to decode a plurality of encrypted data segments fromthe plurality of sets of encoded in slices. The DS processing mayde-append (parse) the virtual DSN address from the encoded data slices(e.g., source name and/or slice names). In an example, the DS processingmay compare the received DSN address to the sent DS address. The DSprocessing may validate the slices when the comparison is favorable(e.g., the same).

At step 228, the DS processing decrypts each encrypted data segment ofthe plurality of encrypted data segments in accordance with theoperational parameters to produce a plurality of received encoded datasegments. Note that the DS processing may decrypt each segment with adifferent decryption algorithm and/or different key. At step 230, the DSprocessing decodes the plurality of received encoded data segments inaccordance with the operational parameters (e.g., the decodingalgorithm) to produce a plurality of data segments. Note that the DSprocessing may select a decoding algorithm based on the securityrequirements. For example, the DS processing selects a stronger encodingalgorithm (e.g., to provide better error correction for encrypted data)may have been used when the security indicator indicates that a higherlevel of security is required. At step 232, the DS processing aggregatesthe plurality of data segments to produce an encrypted data object. Atstep 234, the DS processing decrypts the encrypted data object inaccordance with the operational parameters to produce the data object.At step 236, the DS processing sends the data object to the requester.

FIG. 15 is another schematic block diagram of another embodiment of acomputing system. As illustrated, the system includes a user device 238,at least one dispersed storage network (DSN) memory 22, and a secretrecovery agent(s) 240. The user device includes data 242 (e.g., in abuffer), an encryptor 244, a DS processing 34, a data access key 246, anencryptor 248, a local memory 250, a password 252, a decryptor 254,another DS processing 34, a decryptor 256, a data 243, a key storage258, and a key retrieval function 260. The data 242 may include any typeof digital information such as text, pictures, video clips, records,database information, message board information, links, contacts, etc.The data access key 246 may be an entered managed encryption key or arandom encryption key (e.g., based on a random number generator).

In an example of operation, the encryptor 244 encrypts the data 242 inaccordance with operational parameters (e.g., type of encryptionalgorithm) utilizing the data access key 246 to produce encrypted data.The DS processing 34 encodes the encrypted data in accordance with theoperational parameters (e.g., pillar width, read threshold, encodingmethod, compression, further encryption, DSN memory locations for thepillars) to produce encoded data slices. The DS processing sends theencoded data slices to the DSN memory for storage therein.

In an example of operation, the encryptor 248 encrypts the data accesskey 246 in accordance with the operational parameters utilizing thepassword 252 as an encryption key to produce an encrypted data accesskey. The encryptor may receive the password 252 from the user device 238or retrieve it from memory. The user device 238 saves the data accesskey 246. In an instance, the encryptor 248 stores the encrypted dataaccess key in the local memory 250. In another instance, the key storagefunction 258 saves the data access key 246 in the DSN memory 22 asdescribed in more detail below. In yet another instance, the data accesskey 246 is saved in both the DSN memory 22 and in the local memory 250.In a retrieval scenario, decryptor 254 decrypts the encrypted dataaccess key retrieved from the local memory 250 in accordance with theoperational parameters utilizing the password 252 as a decryption key toproduce a data access key 262.

In an example of operation, the key storage function 258 encrypts thedata access key 246 utilizing a second key to produce an encrypted key264. Note that the second key may be a random key or a predeterminedstored and managed key. The key storage function 258 sends the encryptedkey 264 (e.g., as key slices) with a store command to the DSN memory 22to store the encrypted key 264. In addition, the key storage function258 may store a virtual DSN address of the storage location of theencrypted key 264 in a vault (e.g., operational parameters) and/or tablelinked to a virtual DSN address of the location of the stored encrypteddata. The key storage function 258 creates a plurality of secrettransformations 266 based on the second key. The secret transformations266 may be Shamir shared secrets and/or distributed storage slices. Thekey storage function 258 uniquely encrypts each of the plurality ofsecret transformations 266 such that each may be subsequently decryptedby one of the secret recovery agents 240. Alternatively, the key storagefunction 258 may encode the secret transformations 266 in accordancewith the operational parameters to produce encoded transformationslices. The key storage function 258 sends the encoded transformationslices with a store command to the DSN memory 22 to store the secondkey. In addition, the key storage function 258 may store a virtual DSNaddress of the location of the stored second key in a vault (e.g.,operational parameters) and/or table linked to the virtual DSN addressof the location of the stored encrypted data and/or of the stored secondkey.

In a data recovery example of operation, the DS processing 34 retrieves,de-slices, and decodes the encoded data slices of the encrypted datafrom the DSN memory 22 in accordance with the operational parameters(e.g., pillar width, read threshold, decoding method, de-compression,further decryption, DSN memory locations for the pillars) to produce theencrypted data. The decryptor 256 decrypts the encrypted data utilizinga reproduced version of the data access key 246 to produce data 243. Inan instance, the decryptor 256 decrypts the encrypted data utilizing thedata access key 262 recovered from local memory 250 in accordance withthe operational parameters (e.g., decryption algorithm) to produce thedata 243. In another instance, the decryptor 256 decrypts the encrypteddata utilizing a data access key 263 recovered from the DSN memory 22and in accordance with the operational parameters (e.g., decryptionalgorithm) to produce the data 243. The key retrieval function 260provides the data access key 263 as described below.

In an example of operation, the key retrieval function 260 sends arequest to the secret recovery agents 240 to return the secrettransformations 268. The secret recovery agents 240 retrieve slices ofthe secret transformations 268 from the DSN memory 22, de-slice anddecode the slices in accordance with an error coding dispersal storagefunction and in accordance with the operational parameters to produceencrypted secret transformations. The secret recovery agents 240 decryptthe encrypted secret transformations utilizing a unique decryptionparameter associated with each of the plurality of the secret recoveryagents (e.g., their unique private key) to produce the secrettransformations 268. In addition, the secret recover agents 240 mayre-encrypt each of the secret transformations 268 (e.g., with a publickey for the key retrieval function) to produce the secrettransformations 268 as re-encrypted secret transformations. Next thesecret recovery agent 240 sends the secret transformations 268 to thekey retrieval function 260. The method of operation of the secretrecovery agents 240 is discussed in greater detail with reference toFIGS. 16 and 19.

The key retrieval function 268 receives the secret transformations 268from the secret recovery agents 240 and decrypts the secrettransformations 268 (e.g., with a key retrieval function private key) toproduce decrypted secret transformations. The key retrieval function 260de-transforms a threshold number of the decrypted secret transformationsinto a secret, which is the second key. In an instance, thede-transformation is a shared secret decoding function (e.g., a Shamirshared secret algorithm). In another instance, the transformation isde-slicing and decoding slices utilizing an error coding dispersalstorage function to produce the secret in accordance with theoperational parameters.

The data retrieval example continues where the key retrieval function260 retrieves, de-slices, and decodes encoded key slices of theencrypted key 270 from the DSN memory 22 in accordance with theoperational parameters to produce the encrypted key 270. The keyretrieval function 260 decrypts the encrypted key 270 utilizing thesecond key (e.g., the secret from the secret transformations) to producethe data access key 263. The decryptor 256 decrypts the encrypted datafrom the DSN memory 22 utilizing the data access key 263 in accordancewith the operational parameters (e.g., decryption algorithm) to producethe data 243. The method of operation of the key storage function 258,the secret recovery agents 240, and the key retrieval function 260 arediscussed in greater detail with reference to FIGS. 16-19.

FIG. 16 is a schematic block diagram of an embodiment of an encryptionkey storage and retrieval system. As illustrated, the system includes akey storage function 258, a key retrieval function 260, a plurality ofagents a-c, and a DSN memory 22. As illustrated, the key storagefunction 258 includes an encryptor 272, a DS processing 34, a random key274, a transform function 276, a plurality of encryptors 278, and aplurality of DS processing 34. As illustrated, the key retrievalfunction 260 includes a DS processing 34, a decryptor 288, atransformation function 286, and a plurality of decryptors 284. Asillustrated, each of the agents a-c includes a DS processing 34, adecryptor 280, and an encryptor 282.

In an example of operation, the encryptor 272 encrypts a data access key246 utilizing the random key 74 as an encryption key and in accordancewith the operational parameters (e.g., encryption algorithm) to producean encrypted data access key. The DS processing 34 encodes the encrypteddata access key utilizing an error coding dispersal storage function andin accordance with operational parameters (e.g., pillar width, readthreshold, write threshold, encoding algorithm, extra encryption,compression, DSN address, etc.) to produce an encrypted key 264 asencoded key slices. The DS processing 34 sends the encrypted key 264(e.g. the encoded key slices) to the DSN memory 22 with a store commandfor storage therein. In addition, the DS processing 34 may update avirtual DSN address to physical location table (e.g., a portion of theoperational parameters) with DSN memory locations of where the keyslices of the encrypted key 264 are stored.

In an example of operation, the transform function 276 transforms therandom key 274 in accordance with the operational parameters to producesecret transforms. In an instance, the transformation function 276produces a plurality of Shamir shared secrets. In another instance, thetransformation function 276 produces a plurality of encodedtransformation slices. As illustrated, the transformation function 276produces secret transformations a-c such that three agents subsequentlyretrieve the secret transformations a-c. Note that two of the threesecret transformations may reproduce the secret (e.g., the random keyvalue) when a threshold number is two.

In an example of operation, the encryptors 278 encrypt the secrettransformations utilizing public keys a-c to produce secrettransformations a-c. For example, encryptor 278 utilizes public key b toencrypt secret transformation b that is subsequently retrieved anddecrypted by agent b. The set of DS processing 34 encodes the secrettransformations in accordance with the operational parameters to produceencoded transformation slices as the secret transformations a-c. The setof DS processing 34 sends the secret transformations a-c with a storecommand to the DSN memory 22 for storage therein. For example, the thirdDS processing 34 sends encoded transformation slices of the secrettransformation c to the DSN memory 22. In addition, the DS processingmodule 34 may update the virtual DSN address to physical location table(e.g., a portion of the operational parameters) with a DSN memorylocations where each of the secret transformations a-c slices arestored. Note that the table may link the data, the encrypted key, andthe secret transformations.

In a data retrieval example of operation, the key retrieval function 260sends a request for secret transformations of a present encrypted keyretrieval sequence to the agents a-c. The operation of the agents a-c isdiscussed below. The decryptors 284 receive encrypted secrettransformations from the agents a-c and decrypt the encrypted secrettransformations utilizing a private key 1 associated with the keyretrieval function 260 to produce secret transformations. Thetransformation function 286 transforms a threshold number of the secrettransformations in accordance with the operational parameters to producea secret (e.g., the random key 274). In an instance, the transformationfunction utilizes a Shamir shared secret method. In another instance,the transformation function utilizes an error coding dispersal storagefunction to transform slices into the secret. The DS processing 34 ofthe key retrieval function 260 retrieves an encrypted key 270 from theDSN memory 22. The DS processing 34 decodes the encrypted key 270utilizing an error coding dispersal storage function to produce anencrypted key. The decryptor 288 decrypts the encrypted key utilizingthe random key 274 to produce the data access key 263.

In the retrieval example of operation, the DS processing 34 in agent bdetermines storage locations in DSN memory 22 of the secrettransformation it may retrieve based on the operational parametersand/or information contained in the retrieval request. The DS processingretrieves, de-slices, and decodes secret transformation b to produce theencrypted secret transformation. In an instance, DS processing 34 ofagent b produces the encrypted secret transformation b. Note that thesystem may include any number of agents to recover secrettransformations. In an instance, one agent retrieves one secrettransformation. In another instance, one agent retrieves more than onesecret transformation. The decryptor 280 decrypts the encrypted secrettransformation utilizing the unique private key of the associated agentbased on the operational parameters (e.g., decryption algorithm) toproduce the secret transformation. For example, agent c utilizes privatekey c to decrypt the encrypted secret transformation c. The encryptor282 encrypts the secret transformation utilizing the public key of thekey retrieval function 260. For example, the encryptor 282 of agent bencrypts the secret transformation b utilizing the public key 1 of thekey retrieval function 260. The agent sends the encrypted secrettransformation to the decryptor 284 of the key retrieval function 260that requested the secret transformation.

FIG. 17 is a flowchart illustrating an example of storing an encryptionkey. The method begins with step 290 where a dispersed storage (DS)processing (e.g., a processing module of a DS processing module)receives a data access key and a command to store the data access key ina dispersed storage network (DSN) memory. The data access key may bereceived from any of a user device, a DS processing unit, a storageintegrity processing unit, a DS managing unit, and a DS unit. At step292, the DS processing determines a random key. Such a determination maybe based on a random number generator. At step 294, the DS processingdetermines operational parameters where the operational parameters mayinclude one or more of pillar width n, read threshold k, writethreshold, encoding algorithm, encryption algorithm, compression method,an agent ID list, public keys associated with the agents, public/privatekey pairs for the DS processing, DSN addresses of a data objectassociated with the data access key, DSN address of the encrypted dataaccess key storage, and DSN address for the storage of the secrettransformations. Such a determination may be based on one or more of auser vault lookup, a command, a request, a predetermination, a dataobject ID, a data type, a priority indicator, a security indicator, anda performance indicator.

The method continues at step 296 where the DS processing encrypts thedata access key utilizing the random key and in accordance with theoperational parameters to produce an encrypted data access key. At step298, the DS processing encodes the encrypted data access key utilizingan error coding dispersal storage function and in accordance with theoperational parameters to produce encoded key slices. At step 300, theDS processing sends the encoded key slices with a store command to adispersed storage network (DSN) memory for storage therein.

At step 302, the DS processing transforms the random key in accordancewith the transformation function to produce a plurality of secrettransformations. In an instance, the DS processing transforms the randomkey in accordance with a Shamir shared secret transformation to producea plurality of Shamir shared secret transformations. In anotherinstance, the DS processing transforms the random key utilizing an errorcoding dispersal storage function transform and in accordance with theoperational parameters to produce a plurality of sets of encodedtransform slices.

At step 304, the DS processing determines an encryption key to uniquelyencrypt each of the plurality of secret transformations based on theoperational parameters (e.g., which agents and public keys). Forexample, the first secret transformation may be encrypted with a publickey associated with a first agent when the first secret transformationis to be subsequently decrypted by the first agent. In another example,the second secret transformation may be encrypted with a public keyassociated with a second agent when the second secret transformation isto be subsequently decrypted by the second agent. At step 306, the DSprocessing encrypts each secret transformation with an associatedencryption key. Note that only the agent the secret transformation istargeting can subsequently decrypt the secret transformation. At step308, the DS processing encodes the encrypted secret transformations ofthe encrypted secret transformations utilizing the error codingdispersal storage function and in accordance with the operationalparameters to produce encoded encrypted transformation slices. At step310, the DS processing sends the encoded encrypted transformation sliceswith a store command to the DSN memory for storage therein.

FIG. 18 is a flowchart illustrating an example of retrieving anencryption key. The method begins with step 312 where a dispersedstorage (DS) processing receives a data access key request from arequester to retrieve a data access key from a dispersed storage network(DSN) memory. The data access key request may be received from any of auser device, a DS processing unit, a storage integrity processing unit,a DS managing unit, and a DS unit. At step 314, the DS processingdetermines operational parameters wherein the operational parameters mayinclude one or more of pillar width n, read threshold k, writethreshold, encoding algorithm, encryption algorithm, compression method,an agent ID list, public keys associated with the agents, public/privatekey pairs for the DS processing, DSN addresses of a data objectassociated with the data access key, DSN address of the encrypted dataaccess key storage, and DSN address for the storage of the secrettransformations. Such a determination may be based on one or more ofinformation in the retrieval request, a user vault lookup, a command, arequest, a predetermination, a data object ID, a data type, a priorityindicator, a security indicator, and a performance indicator.

At step 316, the DS processing determines which agents to request secrettransformations based on the operational parameters (e.g., the agent IDlist). The DS processing sends a secret transform retrieval request toat least a threshold number of agents. Note that the request may beencrypted with the unique public key of each of the agents and mayinclude the public key of the requester for the subsequent response. Inan example, the DS processing may also include a hash of the public keyassociated with the requester to pre-validate the request.

At step 318, DS processing receives a validation request from each agentwhere the elevation request includes a request for the hash of thepublic key associate with the requester. The DS processing calculatesthe hash of the requester public key and sends the hash to the agent tovalidate the request. At step 320, the DS processing receives encryptedsecret transformations from the agents in response to the validationstep. At step 322, the DS processing decrypts the encrypted secrettransformations utilizing a private key (e.g., paired to the public key)of the requester and in accordance with the operational parameters(e.g., decryption algorithm) to produce the secret transformations.

At step 324, the DS processing transforms at least a threshold number ofthe secret transformations to produce the random key. In an instance,the DS processing transforms the secret transformations utilizing aShamir shared secret method. In another instance, the DS processingtransforms the secret transformations utilizing an error codingdispersal storage function and in accordance with the operationalparameters. At step 326, the DS processing retrieves encoded encrypteddata access key slices by sending a retrieval command to a DSN memoryaddress. At step 328, the DS processing receives the slices and decodesthe slices in accordance with an error coding dispersal storage functionand in accordance with the operational parameters to produce one or moredata segments of the encrypted data access key. The DS processing mayaggregate the one or more data segments of the encrypted data access keyto produce the encrypted data access key when there is more than onedata segment. At step 330, the DS processing decrypts the encrypted dataaccess key utilizing the random key. At step 332, the DS processingsends the data access key to the requester.

FIG. 19 is a flowchart illustrating an example of retrieving a secrettransformation. The method begins with step 334 where a DS processingreceives a secret transformation retrieval request from a requester toretrieve a secret transformation from a dispersed storage network (DSN)memory. The secret transformation retrieval request may be received fromany of a user device, a DS processing unit, a storage integrityprocessing unit, a DS managing unit, and a DS unit. The secrettransformation retrieval request may include request informationincluding one or more of a data object name, a DSN address of the secrettransformation, a public key of the requester, and a hash of a publickey of the requester.

At step 336, the DS processing sends a validation request to therequester where the validation request includes a request for the hashof a public key associated with the requester. The DS processingcompares a received hash to a calculated hash of the requester's publickey to validate the request. The method ends with an error when thecomparison reveals that the received hash is not substantially the sameas the calculated hash of the requester's public key. The methodcontinues to step 338 when the key is processing determines that thereceived hash is substantially the same as the calculated hash of therequester's public key.

At step 338, the DS processing determines operational parameters whereinthe operational parameters may include one or more of pillar width n,read threshold k, write threshold, encoding algorithm, encryptionalgorithm, compression method, an agent ID list, public keys associatedwith the agents, public/private key pairs for the DS processing, DSNaddresses of a data object associated with the data access key, DSNaddress of the encrypted data access key storage, and DSN address forthe storage of the secret transformations. Such a determination may bebased on one or more of the request information, a user vault lookup, acommand, a request, a predetermination, a data object ID, a data type, apriority indicator, a security indicator, and a performance indicator.

At step 340, the DS processing retrieves encoded secret transformationslices by sending a retrieval command to the DSN memory for. At step342, the DS processing receives and decodes the slices utilizing anerror coding dispersal storage function and in accordance with theoperational parameters to produce one or more data segments of anencrypted secret transformation. At step 344, the DS processing decryptsdata segments of the encrypted secret transformation utilizing theprivate key of the agent and aggregates data segments in accordance withthe operational parameters to produce the secret transformation.

At step 346, the DS processing determines a public encryption key of therequester based on the operational parameters. At step 348, the DSprocessing encrypts the secret transformation utilizing the public keyof the requester to produce an encrypted secret transformation. At step350, the DS processing sends the encrypted secret transformation to therequester (e.g., the key retrieval function).

As may be used herein, the terms “substantially” and “approximately”provides an industry-accepted tolerance for its corresponding termand/or relativity between items. Such an industry-accepted toleranceranges from less than one percent to fifty percent and corresponds to,but is not limited to, component values, integrated circuit processvariations, temperature variations, rise and fall times, and/or thermalnoise. Such relativity between items ranges from a difference of a fewpercent to magnitude differences. As may also be used herein, theterm(s) “operably coupled to”, “coupled to”, and/or “coupling” includesdirect coupling between items and/or indirect coupling between items viaan intervening item (e.g., an item includes, but is not limited to, acomponent, an element, a circuit, and/or a module) where, for indirectcoupling, the intervening item does not modify the information of asignal but may adjust its current level, voltage level, and/or powerlevel. As may further be used herein, inferred coupling (i.e., where oneelement is coupled to another element by inference) includes direct andindirect coupling between two items in the same manner as “coupled to”.As may even further be used herein, the term “operable to” or “operablycoupled to” indicates that an item includes one or more of powerconnections, input(s), output(s), etc., to perform, when activated, oneor more its corresponding functions and may further include inferredcoupling to one or more other items. As may still further be usedherein, the term “associated with”, includes direct and/or indirectcoupling of separate items and/or one item being embedded within anotheritem. As may be used herein, the term “compares favorably”, indicatesthat a comparison between two or more items, signals, etc., provides adesired relationship. For example, when the desired relationship is thatsignal 1 has a greater magnitude than signal 2, a favorable comparisonmay be achieved when the magnitude of signal 1 is greater than that ofsignal 2 or when the magnitude of signal 2 is less than that of signal1.

While the transistors in the above described figure(s) is/are shown asfield effect transistors (FETs), as one of ordinary skill in the artwill appreciate, the transistors may be implemented using any type oftransistor structure including, but not limited to, bipolar, metal oxidesemiconductor field effect transistors (MOSFET), N-well transistors,P-well transistors, enhancement mode, depletion mode, and zero voltagethreshold (VT) transistors.

The present invention has also been described above with the aid ofmethod steps illustrating the performance of specified functions andrelationships thereof. The boundaries and sequence of these functionalbuilding blocks and method steps have been arbitrarily defined hereinfor convenience of description. Alternate boundaries and sequences canbe defined so long as the specified functions and relationships areappropriately performed. Any such alternate boundaries or sequences arethus within the scope and spirit of the claimed invention.

The present invention has been described, at least in part, in terms ofone or more embodiments. An embodiment of the present invention is usedherein to illustrate the present invention, an aspect thereof, a featurethereof, a concept thereof, and/or an example thereof. A physicalembodiment of an apparatus, an article of manufacture, a machine, and/orof a process that embodies the present invention may include one or moreof the aspects, features, concepts, examples, etc. described withreference to one or more of the embodiments discussed herein.

The present invention has been described above with the aid offunctional building blocks illustrating the performance of certainsignificant functions. The boundaries of these functional buildingblocks have been arbitrarily defined for convenience of description.Alternate boundaries could be defined as long as the certain significantfunctions are appropriately performed. Similarly, flow diagram blocksmay also have been arbitrarily defined herein to illustrate certainsignificant functionality. To the extent used, the flow diagram blockboundaries and sequence could have been defined otherwise and stillperform the certain significant functionality. Such alternatedefinitions of both functional building blocks and flow diagram blocksand sequences are thus within the scope and spirit of the claimedinvention. One of average skill in the art will also recognize that thefunctional building blocks, and other illustrative blocks, modules andcomponents herein, can be implemented as illustrated or by discretecomponents, application specific integrated circuits, processorsexecuting appropriate software and the like or any combination thereof.

What is claimed is:
 1. A method for securely distributing a profileregarding a user device to another user device of a dispersed storagenetwork (DSN), the method comprises: encrypting a profile using a key toproduce an encrypted profile; encoding the encrypted profile inaccordance with a dispersed storage error encoding function to produce aset of encoded profile slices; outputting the set of encoded profileslices to storage units of the DSN for storage therein; encoding the keyin accordance with an error encoding function to produce a set of securekey portions; outputting the set of secure key portions to a set of userdevices of the DSN, wherein user devices of the set of user devices areseparate devices of the DSN than storage units of the DSN, wherein afirst user device of the set of user devices receives and stores a firstsecure key portion of the set of secure key portions and a second userdevice of the set of user devices receives and stores a second securekey portion of the set of secure key portions; and obtaining the profileby one of the set of user devices by: retrieving a threshold number ofthe set of secure key portions from the set of user devices; recoveringthe key from the threshold number of the set of secure key portions;retrieving a decode threshold number of the set of encoded profileslices from the DSN; decoding the decode threshold number of the set ofencoded profile slices to recover the encrypted profile; and decryptingthe encrypted profile using the key to recover the profile.
 2. Themethod of claim 1, wherein the encoding the key further comprises:encoding the key in accordance with the error encoding function, whereinthe error encoding function includes one of the dispersed storage errorencoding function and another dispersed storage error encoding function,and wherein the set of secure key portions includes a set of encoded keyslices.
 3. The method of claim 1, wherein the encoding the key furthercomprises: encoding the key in accordance with the error encodingfunction, wherein the error encoding function includes a Shamir sharefunction and wherein the set of secure key portions includes a set ofsecret key shares.
 4. The method of claim 1, wherein the set of userdevices comprises at least one of: one or more storage units; one ormore user devices; one or more storage integrity units; and one or moremanaging units.
 5. The method of claim 1 further comprises: outputtingthe set of encoded profile slices to the storage units of the DSN forstorage therein; and outputting the set of secure key portions to atleast some of the storage units for storage therein.
 6. The method ofclaim 1 further comprises: outputting the set of encoded profile slicesto the set of user devices for storage therein.
 7. The method of claim1, wherein the profile comprises one or more of: authenticationinformation; permissions; a name; personal information; password; and apicture.
 8. A dispersed storage network (DSN) comprises: a plurality ofuser devices, wherein a first user device of the plurality of userdevices securely distributes a profile regarding the first user deviceto another user device of the plurality of user devices; the first userdevice including a first interface, a first memory, and a firstprocessing module operably coupled to the first interface and the firstmemory, wherein the first processing module is operable to: encrypt theprofile using a key to produce an encrypted profile; encode theencrypted profile in accordance with a dispersed storage error encodingfunction to produce a set of encoded profile slices; output, via thefirst interface, the set of encoded profile slices to storage units ofthe DSN for storage therein; encode the key in accordance with an errorencoding function to produce a set of secure key portions; output, viathe first interface, the set of secure key portions to a set of userdevices of the plurality of user devices, wherein a first user device ofthe set of user devices receives and stores a first secure key portionof the set of secure key portions and a second user device of the set ofuser devices receives and stores a second secure key portion of the setof secure key portions; and the second user device including a secondinterface, a second memory, and a second processing module operablycoupled to the second interface and the second memory, wherein thesecond processing module is operable to obtain the profile by:retrieving, via the second interface, a threshold number of the set ofsecure key portions from the set of user devices, wherein user devicesof the set of user devices are separate devices of the DSN than thestorage units of the DSN; recovering the key from the threshold numberof the set of secure key portions; retrieving, via the second interface,a decode threshold number of the set of encoded profile slices from theDSN; decoding the decode threshold number of the set of encoded profileslices to recover the encrypted profile; and decrypting the encryptedprofile using the key to recover the profile.
 9. The DSN of claim 8,wherein the first processing module is further operable to: encode thekey in accordance with the error encoding function, wherein the errorencoding function includes one of the dispersed storage error encodingfunction and another dispersed storage error encoding function, andwherein the set of secure key portions includes a set of encoded keyslices.
 10. The DSN of claim 8, wherein the first processing module isfurther operable to: encode the key in accordance with the errorencoding function, wherein the error encoding function includes a Shamirshare function and wherein the set of secure key portions includes a setof secret key shares.
 11. The DSN of claim 8, wherein the set of userdevices comprises at least one of: one or more storage units; one ormore user devices; one or more storage integrity units; and one or moremanaging units.
 12. The DSN of claim 8 further comprises: the firstprocessing module further operable to output, via the first interface,the set of encoded profile slices to the storage units of the DSN forstorage therein; and the second processing module further operable tooutput, via the second interface, the set of secure key portions to atleast some of the storage units for storage therein.
 13. The DSN ofclaim 8 further comprises: the first processing module further operableto output, via the first interface, the set of encoded profile slices tothe set of user devices for storage therein.
 14. The DSN of claim 8,wherein the profile comprises one or more of: authenticationinformation; permissions; a name; personal information; password; and apicture.